When we meet someone we tend to label them in certain ways. "Tall guy" you might think, or "Ugly kid". Lots of work in social psychology suggests that there are some categorisations that spring faster to mind. So fast, in fact, that they can be automatic. Sex is an example: we tend to notice if someone is a man or a woman, and remember that fact, without any deliberate effort. Age is another example. You can see this in the way people talk about others. If you said you went to a party and met someone, most people wouldn't let you continue with your story until you said if it was a man or a woman, and there's a good chance they'd also want to know how old they were too.

Unfortunately, a swathe of evidence from the 1980s and 1990s also seemed to suggest that race is an automatic categorisation, in that people effortlessly and rapidly identified and remembered which ethnic group an individual appeared to belong to. “Unfortunate”, because if perceiving race is automatic then it lays a foundation for racism, and appears to put a limit on efforts to educate people to be “colourblind”, or put aside prejudices in other ways.

Over a decade of research failed to uncover experimental conditions that could prevent people instinctively categorising by race, until a trio of evolutionary psychologists came along with a very different take on the subject. Now, it seems only fair to say that evolutionary psychologists have a mixed reputation among psychologists. As a flavour of psychology it has been associated with political opinions that tend towards the conservative. Often, scientific racists claim to base their views on some jumbled version of evolutionary psychology (scientific racism is racism dressed up as science, not racisms based on science, in case you wondered). So it was a delightful surprise when researchers from one of the world centres for evolutionary psychology intervened in the debate on social categorisation, by conducting an experiment they claimed showed that labelling people by race was far less automatic and inevitable than all previous research seemed to show.

Powerful force

The research used something called a “memory confusion protocol”. This works by asking experiment participants to remember a series of pictures of individuals, who vary along various dimensions – for example, some have black hair and some blond, some are men, some women, etc. When participants’ memories are tested, the errors they make reveal something about how they judged the pictures of individuals – what sticks in their mind most and least. If a participant more often confuses a black-haired man with a blond-haired man, it suggests that the category of hair colour is less important than the category of gender (and similarly, if people rarely confuse a man for a woman, that also shows that gender is the stronger category).

Using this protocol, the researchers tested the strength of categorisation by race, something all previous efforts had shown was automatic. The twist they added was to throw in another powerful psychological force – group membership. People had to remember individuals who wore either yellow or grey basketball shirts, and whose pictures were presented alongside statements indicating which team they were in. Without the shirts, the pattern of errors were clear: participants automatically categorised the individuals by their race (in this case: African American or Euro American). But with the coloured shirts, this automatic categorisation didn't happen: people's errors revealed that team membership had become the dominant category, not the race of the players.

It's important to understand that the memory test was both a surprise – participants didn't know it was coming up – and an unobtrusive measure of racial categorising. Participants couldn’t guess that the researchers were going to make inferences about how they categorised people in the pictures – so if they didn't want to appear to perceive people on the basis of race, it wouldn't be clear how they should change their behaviour to do this. Because of this we can assume we have a fairly direct measure of their real categorisation, unbiased by any desire to monitor how they appear.

So despite what dozens of experiments had appeared to show, this experiment created a situation where categorisation by race faded into the background. The explanation, according to the researchers, is that race is only important when it might indicate coalitional information – that is, whose team you are on. In situations where race isn't correlated with coalition, it ceases to be important. This, they claim, makes sense from an evolutionary perspective. For most of ancestors age and gender would be important predictors of another person's behaviour, but race wouldn't – since most people lived in areas with no differences as large as the ones we associate with “race” today (a concept, incidentally, which has little currency among human biologists).

Since the experiment was published, the response from social psychologists has been muted. But supporting evidence is beginning to be reported, suggesting that the finding will hold. It's an unfortunate fact of human psychology that we are quick to lump people into groups, even on the slimmest evidence. And once we've identified a group, it's also seems automatic to jump to conclusions about what they are like. But this experiment suggests that although perceiving groups on the basis of race might be easy, it is far from inevitable.

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